Process of pyrogenetic decomposition of oils and apparatus therefor



H. SYDNOR June 9 1931.

PROCESS OF PYROGENE'IIC DECOMPOSITION OF OILS AND APPARATUS THEREFORFiled July 6. 1927 Eb W awvemfoz HAROLD SYDA/OR hm (liken m1;

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Patented June 9, 1931 UNITED STATES PATENT OFFICE,

' HAROLD SYDNOR, ELIZABETH, NEW JERSEY, ASSIGNOR T STANDARD OIL DE-VELOPMENT COMPANY, A.- CORPORATION OF DELAWARE PROCESS OF PYBIOGENETICDECOMPOSITION O-F OILS AND APPARATUS THEREFOR Application filed- July 6,1927. Serial No. 203,856.

This invention relates to the cracking of petroleum oil and has for itsobject the reduction or elimination of the tendency of the cracked oilto form carbonaceous deposits in pipes conveying it from the crackingzone.

Apparatus suitable for carrying out my invention is showndiagrammatically in the annexed drawing, in which 1 designates afirebrick setting heated by burner 52. Cracking apparatus of anysuitable form may be provided but it preferably comprises a heatingconduit or coil 3. The coil 3 receives oil by means of inlet pipe 5 fromany source and discharges into pipe 6, which is surrounded by electricheating unit 6w connected to a suitable source of electric current andsurrounded by thermal insulating material 6b. 7

Pipe 6 conducts the heated materials to a digesting or cracking chamber7, for example, a drum covered to prevent substantial loss of heat. Fromthe lower part of drum 7 a pipe 8, equipped with the loaded ablepressure to coil 3 and heated to a cracking temperature by burner 2. Inthe special cracking coil arrangement shown in the drawingthe oil isintroduced through line 5 and passed first through some rows of tub ingin the upper part of the convection heat section of the setting, thenled through the vertical down-flow pipe on the exterior of the furnaceto the lower part of the convection section and passed through severalrows of tubing in countercurrent relation to the flue gases. Hence theoil flows first through the lower row then through the middle row oftubes in the radiant heat section whence it passes through the verticalpipe on the left into the'soaking coils composed of several rows oftubes in the middle part of the convection heat section, hence into theupper row of tubes in the radiant-heat section and finally'into pipe 6.This coil arrangement forms no part of the present invention.

The heated oil and/or oil -vaporpass to the digesting drum 7 and thencethrough pipe 8 and release valve 9 at a lower pressure into rectifyingtower 10. Heretofore under certain conditions of operation, flow throughpipes conveying the product from the cracking zone has been impeded orstopped by the formation of carbonaceous deposits.

I have found that these deposits which are sometimes formed undercertain conditions of operation, may be inhibited or eliminated by theapplication of heat to such pipes. It will be understood that theapparatus shown is illustrative only and that the invention includes theapplication of heat to any pipe or other conductor carrying products ofthe pyrolytic decomposition of petroleum oils from a cracking zone. Theheating should be continued up to the point in the apparatus at whichsubstantial condensation of the vapors takesplace and this may be, forexample, a barometric condenser, a pipe condenser of the conventionaltype or its equivalent or a bubble or fractionating tower in whichcondensation is effected by passing the vapors into a body of liquid.The drum 7 may, for-instance, be eliminated and pipes 6 and 8 may bedirectly connected. While the application of any heat "is beneficial,the heat should preferably be suflicient to maintain the pipe orconductor at a temperature slightly higher than that of the materialsconducted. i I Any suitable means of applying this heat may be utilized.I may surround such pipes by a conductor carrying alternating currentsof high frequency and thereby generate the heat necessary in the wall ofthe pipe by means of eddy current and hysteresis loss,

but I find preferable an electric heating desurrounded by suitableinsulating material to prevent excessive thermal losses. Any other formof apparatus for the pyrolytic decomposition of petroleum oil may beemployed and any other method of applying heat may be used Withoutdeparting from my invention.

What I claim is:

1. The method of minimizing carbonaceous deposits in, pipes carryingcracked petroleum hydrocarbons from a final cracking zone to a point ofcondensation, which comprises the application of electrically generatedheat to such pipes.

2. The method of minimizing deposits in pipes or conductors carryingcracked petroleum hydrocarbons from a digestionzone to a point ofcondensation, which comprises the application of heat to such pipes orconductors, sufficient to maintain the temperature of same slightlyabove that of the vapors conducted.

3. Cracking apparatus which comprises a digestion chamber, means forconducting cracked hydrocarbons from the digestion chamber vto a pointof condensation, means for applying heat to said conducting means.

4. The method of minimizing carbonaceous deposits in pipes or conductorscarrying cracked petroleum hydrocarbons from a digestion zone to afractionating zone, which comprises the application of heat to suchpipes or conductors.

5. Cracking apparatus which comprises a digestion chamber, means forconducting cracked hydrocarbons from the digestion chamber toa point offractionation and means for applying heat to said conducting means. I

HAROLD SYDNOR.

